This invention relates to a solid electrolytic capacitor and a method of fabricating it and, in particular, to technique of sealing and wrapping of the solid electrolytic capacitor using a flat-shaped capacitor element.
Surface mounted type solid electrolytic capacitors are well known in the art. For example, the surface mounted type solid electrolytic capacitor comprises an anode electrode made of valve-action metal such as tantalum, aluminum or the like, a dielectric obtained by oxidizing the valve-action metal serving as a base material of the anode electrode, a conductive layer made of manganese dioxide, a conductive macromolecule or the like firmly formed on the dielectric, and a cathode electrode obtained by laminating a graphite layer or a silver pasted layer on the conductive layer. In such surface mounted type solid electrolytic capacitors, ones each comprising a capacitor element having a configuration of pillar body such as a column or a square pole are well known in the art. As the others, capacitors each using a flat shaped element are disclosed, for example, in Japanese Unexamined Patent Publication Tokkai No. Hei 5-275,290 or JP-A 5-275290. This invention relates to a surface mounted type solid electrolytic capacitor using such flat capacitor element.
Speaking characteristics of conventional surface mounted type solid electrolytic capacitors described above from the point of view of relevance of this invention, any capacitor is covered with an exterior finishing resin body formed by molding the surrounding whole of an element by thermosetting resin.
With this structure, it is difficult to thin thickness of the whole of the capacitor including the exterior finishing resin. In addition, sealing of the exterior finishing resin is not always sufficient.